Tight Bounds for Protocols with Hybrid Security
نویسندگان
چکیده
We define hybrid multi-party computation (HMPC) and hybrid broadcast (HBC) in a model without broadcast channels but assuming a signature scheme and a respective public-key infrastructure (PKI) among the players. The goal is to achieve unconditional (PKIand signature-independent) security up to a certain threshold, and security beyond this threshold under stronger assumptions, namely, that forgery of signatures is impossible and/or that the given PKI is consistent. We give a tight characterization of when HMPC and HBC are possible.
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ورودعنوان ژورنال:
- IACR Cryptology ePrint Archive
دوره 2009 شماره
صفحات -
تاریخ انتشار 2009